A cobpobation of new



May 29, 1923. 1,456,960

7 A. O. AUSTIN S OF CERAMIC AND SIMILAR MATERIALS AND METHOD OF PRODUCING SAME a1 Filed Nov. 17, 1919 2 Sheets-Shut 2 7? 675m?? M We x/awga mca [i 0% Patented May 29, 1923.

UNITED STATES PATENT OFFICE.

ARTHUR O. AUSTIN, OF BARBERTON, OHIO, ASSIGIilOR, BY MESNE ASSIGNMENTS, TO THE OHIO BRASS COMPANY, OF DIANSFIELD, OHIO, A. CORPORATION OF NEW JERSEY.

JOINT FOR ARTICLES OF CERALMIC AND SIMILAR MATERIALS AND METHOD OF PRODUCING SAME.

Original application filed November 17, 1919, Serial No. 338,534. Divided and this application filed March 31, 1922. Serial No. 548,331.

To all whom it may concern.

Be it known that I, ARTHUR O. AUSTIN,

a citizen of the United States, residing at Bai'berton, county of Summit, and State of Ohio, have invented certain new and useful Improvements in Joints for Articles of Ceramic and Similar Materials and Methods of Producing Same, of which the following is a specification.

This invention has for its object the provision of joints or connections of the character named which shall be of improved construction and operation and the provision of an improved method of producing such joints.

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawings and described in the following specification and 2" in the steps of the process illustrated in the drawings and described in the specification.

The invention is more particularly pointed out in the appended claims.

The present application is a division of 25 application, Serial No. 338,534, filed November 17, 1919.

In the drawings Fig. l is a section of a portion of an insulator illustrating one step in the process of forming the joint comprised in the present invention;

Fig. 2 is a similar view showing a different step in the process;

Figs. 3 and 4 are similar to Figs. 1 and 1* 2 illustrating the application of the process to a difierent form of insulator;

Fig. 5 is a section of an insulator illustrating the application of the process in a slightly different manner;

Fig. 6 is a section of a portion of an insulator showing a different modification of the invention; and

Figs. 7 and 8 show other forms of the invention.

. Broadly described. the invention comrises the joining of two parts composed of ceramic or similar material to one another by fusion at a plurality of limited points of contact.

The invention also contemplates the regu' lation of the closeness of the fit between the parts by proportioning the relative shrinkage or expansion of the parts during firing.

The invention is especially applicable to articles made of ceramic material, such as porcelain and vitreous insulators, tile, brick and other articles of like nature. In joining such articles together it is frequently desired to provide an elastic joint to prevent injury due to unequal expansion and contraction and also to properly distribute forces transmitted from one part to another. Where articles, such as insulators for instance, have had their parts connected together by lazing material which melts in firing and fills the space between the parts, great trouble has been experienced from cracking or dunting of the parts in all but the very small insulators. This has revented commercial success of glaze filled insulators, and other methods of joining parts have had to be resorted to.

In the present invention, a glaze joint having an open mechanical structure is produced, which afi'ords elasticity in the joint and overcomes the difficulties previously experienced. Results soughtmay be-secured in a large variety of ways, some of which are illustrated and described herein, but it.

is understood that the invention is not limited to the specific forms shown and described.

In the process of forming the joint, it is I sometimes desirable to cause the connected surfaces to approach one another more closely durin the firing process.

Figs. 1 an 2 illustrate two stages in the formation of such a joint. In these figures an internal part 1 is provided with a corrugated surface'2 which fits into an opening in an outerpart 3 having an interior corrugated surface 4. Before the parts are fired the inner part 1 is smaller than its surrounding part 3 so that the corrugations of the two will pass one another to permit the parts to be assembled, as shown in Fig. 1. The outer part is made of material which has a greater shrinkage in firing than the inner part so that after the two arts have been fired they will be brought c oser together, as illustrated in, Fig. 2. The dif ference in the amount of contraction of the two parts may rg'qplated' ;by thd's'composi tion of th'e'c'lafy of which the' parts are made in a manner Well known to those skilled in the-art, or,-the; inner part may be partially fired, prior. toassembly, so that it has already partially or totally shrunk when the two parts are placed together; this will cause agreateri shrinkage' ofzthe outer part than the inner part in firing, and will produce the same result as where the outer part is madeof 'materialhaving a greater shrink age than the inner part.

Figs. 3 and 4 illustrate similar steps to those described inconnection and 2, but'in this casetlie inne part1 iiistead of being provided with corrugations '2 is threadd"as shown at '5, the external threads on the part 1 being arranged to mesh n'ith'in-ternalthreads G'on the part3. lVith' this arrangement itis not necessary for the points of the threads to pass one another in assenib'lingthe partshut the two' parts canj'bethreaded together byafr'elative rotation. Th'e'j'oint willbe loose, however, until the parts ar'firec'lg-"after which they will-be in close contact, asilhistrated ih g 4: v

In Fig, 5 an internalfnember 8 fits into a cap'9 'whichis provided-with projections 10 on its inner surface. I A supplemental cap 11 is placed over 'the'eXternaImemberB, and the 's'pace-betweeri the parts 9 and 11" may be packed witha loose'jmaterial, such as quartz sand to prevent the parts 9*and .11 from being fused togetlieri'n firing andto transmit pressure from the part 11 to the part 9. The part'.1'1 is m'ade :0 "material. which, has a relatively high shiinkagei'fin' firing so that it will exert pressureo'nthe'part 9 and cause the projection 11' to be pressed closely into contact with the surface of the inner member 9. Before the parts'arc fired,.onc or the other. or both of the adjacent surfaces of the members 8 and 9 is covered with a glaze, which, during the firing operation will fuse the contacting points of the projections 10 to the outer surfac'of the interior member This will proridea jointhetweeu the members. 8 and 9"wliich is ofopen mechanicalstructu're and irliichiwill afl'ord sufficient resiliency between the two parts to overcome dangerous stresses which. might beset up by unush'allcontraction"or e'zipansion if solid glaze were used for connecting the parts. The fact that thc' oute rfmember is pressed into' e oagemeiitnrith the inner one during the firmfgqh the'coiitraction of the cap 10 insures a'ii nioii oflthe projections 10 with themenibe'rB and prevents any flaring of theexternalmeniberfaway from the innerpartj This method of contraction permits the use hf a, very small. quantity of glaze, as

it is unnecessary to provide amexcess of glaze material to take up inequalities. All

1,4.5o,9eo

the glaze necessary is an exceedingly thin coat on the surface, so that any; difference in the coelli'cient of'expan'sionof the glaze will have little or no effect on the adjacent body portions. v V In Fig. 6 an internal member 12 is provided with projections 13 which maybe formed by ribbing or knurling the surface of the internal member. or maybe produced in a. variety of ways. An external part 14 is titted over the part 13 and ma be made of material which will have a greater shrinkage in firing than part 12, so that the projections 13 will be pressed firmly into con tact with the innersurface of the member 14 during firing. Instead of using material that will shrink differently, the parts may be caused to bear closely on one another in firing by shaping the parts so that the weight of. one will tend' to bring it closer to the other. This will be secured ifthe contacting surfaces are tapered and they will "slide together during the firing operation. Sufficient glaze is provided between .the two surfaces, either by'glazing one or the other, or both, of the surfaces, so that when the parts are fired the projections 13 on the member 12 will be fused to the inner surface of the member 14.150 form a resilient fused; glazed joint.

Figs. T and 8-show internal members 15 and external members 16 which are caused to come into contact during firing in a manner similar to that described in connection with Fig. 6. In Fig. 7 the external member 16 is provided with circularribs l't' which are pressed into the material in the member 15 during the firingproce'ss and fused to the member in a manner similar tothat dc"- v scribed. In Fig. 8 the projections 18 instead of being circular ribs. as shown in Fig. 7, are in the form of threads. so that the two parts maybe screwed together. prior to firmg. if desired. The parts may be so proportioned. however, that they will go to-- gather readily before firing and the outer part will contract upon the inner part to cause the threaded projections 18 to imbed themselves slightly in the inner member in a manner similar to that described in-connection with Fig. 7. If the pieces are made to cause the projections on one to be imbedded sufliciently into the other togivemechanical strength, no glaze is necessary. The ribs or irregular surface has the advantage that it will imbed while.the mate-. rial is soft during the firing process and form an interlock. The smaller section of. the ribs or' irregular projectionsfyield and are not so likel to cause damage to the outer part during the contracting period. The two surfaces may have any degree of contact by applyingthe glaze or fusing material in spots on thesurfacc which only partially cover same.

Where it is desirable to form a conducting surface in the joint for the distribution of electrostatic stress, this can be done by pouring a plating or metallizing solution into the porous joint, such as a silvering solution, or by introducing into the joint a composition which will remain or become conducting during the burning or firing of the parts.

Where it is desirable to prevent a discharge in the spaces and it is not desirable to use a conducting material, the open space in the joint may be filled with an insulating material, such as was, parafiine, or oil, or asphaltum.

I claim I. In combination, a plurality of ceramic bodies having connection with one anotherat a plurality of points of limited extent, said bodies being fused to one another at their points of connection to provide a yielding joint.

2. In combination, a pair of ceramic bodies having adjacent surfaces, projections on one of said surfaces having limited points of contact with the other thereof, said projections being fused to said last-mentioned surface at said limited points of contact, to form a, resilient joint between said bodies.

3. The process of uniting two ceramic bodies which have unequal shrinkage when firing, comprising the steps of assembling the bodies, introducing glazing material between the bodies and firing the bodies to cause one to shrink upon the other and to cause them to be fused together by said glazing material.

4. In combination, a pair of vitreous bodies having adjacent surfaces, projecti'ons on one of said surfaces having limited points of contact with the other thereof,

said projections being fused to said last-' mentioned surface at said limited points of contact to form a joint of limited amount of material between said bodies.

.5. In combination, a pair of vitreous bodies, one of which has a part extending into an opening in another, said bodies being composed of material that will shrink unevenly in firing to cause adjacent surfaces thereof to approach one another, and bodies interposed between said surfaces and having portions contacting with said surfaces and impressed therein by the shrinking of said part-s in firing.

6. In combination, a plurality of ceramic bodies having connections with one another at a plurality of points of limited extent, said bodies being fused to one another at their points of connection to provide a yielding joint, and conducting material in said joint.

7. In combination. a pair of ceramic bodies having adjacent surfaces, projections on one of said surfaces having limited points of contact with the other thereof, said projections bein fused to said last-mentioned surface at said limited points of contact to form a resilient joint between said bodies, and a coating of conducting material on one or both of said surfaces 8. In combination, a. pair of vitreous bodies havin adjacent surfaces, pro'ections on one of sai surfaces having limite oints of contact with the other thereof, sai projections being fused to said last-mentioned surface at said limited points of contact to form a resilient joint between said bodies, and means for metallizing said 'oint.

9. An insulator having a pair of vitreous bodies one of which has a part extending into an opening in the other said bodies being composed of material that will shrink unevenly in firing to cause adjacent surfaces thereof to approach one another, and means on one body interlocking with means on the other body to prevent the separation of the parts after firing.

10. An insulator comprising two parts having adjacent surfaces provided with complementary projections and depressions, one of said parts being positioned within the other and the outer part being composed of material having a greater shrinkage in firing than the inner part so that the projections and depressions will form an interlock for said parts after said parts have been fired.

11. An insulator comprising two parts composed of vitreous material and providing adjacent surfaces with interfittin formations thereon, said parts having di ferent shrinkage when fired to cause said surfaces to approach one another and to bring said formations into'interlocking relation to hold said parts together.

12. An insulator comprising two parts formed of vitreous material, one of said parts extending into the other, the ad'acent surfaces of said parts being provid with interfitting formations, the material of the inner part, and means interposed between said surfaces and extendin into indentations therein for holding sai parts together. In testimony whereof I have signed my name to this specification on this 27th day of March, A D. 1922. ARTHUR O, AUSTIN,- 

